输入10个百分制的成绩；

将百分制成绩（0~100）转变为五级分制（优、良、中、及格、不及格）；

输出转变后的5级分制的成绩。-Enter the 10 percentile score　would percentile scores (0 to 100) into a five-point scale (excellent, good, medium, pass, fail)　output transition after five-point score.